The present invention relates to an improvement for a light guide structure for light guide plate and which is used on the important industry regarding light guide plate and illuminating products, and is already used in cellular phones, PDAs, and watches. The light guide structure of the light guide plate of the present invention increases the illumination evenly and the efficiency of the light emitting diode.
The conventional light guide plate technique employs a high refraction light guide plate and several light emitting diodes (LED). There is a light guide structure in a form of several spots on the light guide plate, and the spots illuminate by the light from the light emitting diodes (the light refraction). The technique is used in the market for a period of time and plays a main role in products of the night light kneading boards. Nevertheless, the conventional technique has the following shortcomings:
1. The efficiency of light guiding of the light guide structure is not satisfied, and the density of the light guide structure is limited (the density of the optimum refraction is fixed and cannot be increased as needs), so that the spots and degree of uniformity on the light guide plate are not satisfied.
2. The spot of the light guide structure has to use expensive V-CUT precision machining (making a V-shaped groove in a single light cable by the precision machining device) to made a mold. The use of the V-CUT increases the manufacturing and the product cost.
The primary object of the present invention is to provide an improvement for a light guide structure for light guide plate and increase the illumination and the degree of uniformity. Line-shaped passages are defined in the light guide plate and parallel to the direction of the light. The depth of the passage is shallow close to the source of light and gradually deeper close the remote position from the source of light. This allows the light form the light emitting diodes to be transferred to a remote area that is far away from the source of light so as to increase the illumination and the degree of uniformity. The light-guide efficiency of the light emitting diodes can also be further increased.
Another object of the present invention is to provide an improvement for a light guide structure for light guide plate with uses production technique that is less expensive. The present invention makes line-shaped passages for guiding the light on the light guide plate so that the manufacturers do not need to use expensive and precise molds made by V-CUT so that the manufacturing cost can be reduced.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.